Alarm wrist-watches



R. DITISHEIM ETN- ALARM WRIST-WATCHES March 22, 1960 Filed Feb. l, 19576 Sheeis-Sheet 1 March 22, 1960 R. Dl'rlsHElM ETAI- 2,929,197

ALARM WRIST-WATCHES Filed Fep. 1, 1957 s sheets-sheet 2 March 22, 1960R, DrnsHElM ETAL 2,929,197

ALARM WRIST-WATCHES A y Filed Feb. l, 1957 K 6 Sheets-Sheet 3 March 22,1960 R D|T|5HE1M ETAL 2,929,197

ALARM WRIST-WATCHES Filed Feb. l, 1957 6 Sheets-Sheet 4 22M/fw@ a QMMarch 22, 1,960 R. DmsHElM ETAI- 2,929,197

ALARM WRIST-WATCHES Filed Feb. 1, i915? e sheets-sheet 5 W//-Ilf March22, 1960 R, D|T|SHE|M ETAL 2,929,197

ALARM WRIST-WATCHES Filed Feb. 1, 1957 6 Sheets-Sheet 6 nied StatesALARM WRST-WATCHES Robert Ditisheim and Henri Robert, La Chanx-de-Fonds,Switzerland, assignors to Ditisheim et Cie, Fabriques Vulcain et Volta,La ChauX-de-Fonds, Switzerland, a corporation of Switzerland Ladieswrist-watches are generally smaller than mens. rifheir maximum size isnot determined but horological practice sets it approximately at adiameter of 23 mm. for round movements. For so-called form movements thelargest dimension is habitually less than 23 mm.

li, within this space, the attempt is made to group the components of asimple movement and the components ci an alarm mechanism as has beendone up to now for mens alarm wrist-watche. this can only lead to a veryhad result, owing'to the lack of space. Either the alarm mechanism issacrificed to the movement and me striking becomes delinitelyinsuicient; or the movement is sacriced .to the alarm and becomes verysmall, very costly and unprecise; or else a compromise which is just asbad is reached between these two extremes. l'n particular, a hammer ofsmall volume Vgives a striking duration which is notably insufficientand a striking frequency which is Vso rapid that it sti'les the sonorityof the membrane. in addition, it is often impossible to position thebanking pin as it should be situated, owing to lack of space, or elsebecause there is generally an incompatibility between ,thepossible,emplacements for the hammer those required to enable themembrane to be vibrated in a favourable manner.

The aim of the present invention is to eliminate these obstacles in alarge measure and to furnish a construction which can be used to obtaina ladys alarm wristwatch. v

its object is a wrist-watch, for instance for ladies, comprising analarm hammer `and which is characterized in that the ellective orstriking part of this hammer moves permanently above at least one of thefollowing components: balance, balance staff, lever of the movement,escape wheel of the movement, barrel of the movement, barrel Vof thealarm, gears of the movemengandin that the upper level of this part doesnot project beyond the upper plane ofthe movement so that the presenceof this hammer within the thickness of the movement does not result inan increase of the height of the latter.

The frequency of the oscillations of the hammer depends, for a givendriving torque, on its moment of inertia in relation toits axis ofrotation. In this moment of inertia vthe radius intervenes in the squarek(in the second power), and consequently the more the matter of thehammer is removed away from its pivoting centre, the easier it is toreduce its mass. We will call eiective part of the hammer that partwhich contributes the most to the formation of its moment of inertia.

The drawing illustrates, by way of examples, nine embodiments of thewatch constituting the object of the iuvention.

Figure 1 is a plan view of the first embodiment, showing a hammeroscillating above the balance pivoting.

Figure 2 is a cross-section along 22 in Fig. 1.

Figure 3 is a plan view of the second embodiment, showing a hammerpassing above both the pivoting of the balance and of one of thebarrels.

Figure 4 is a similar view of a third embodiment.

varent Figure 5 is a plan view of the fourth embodiment, showing thecomponents in their normal position.

Figure 6 is a cross-section along ld-l in Fig. 5.

Figure 7 is a plan view similar to that oi Fig. 5, showing the hammerturned outside.

Figure S is a cross-section along 2--12 in Fig. 7.

Figure 9 is a cross section of a portion of Fig. 2 on an enlarged scaleand with a portion of the hammer and other background parts cut away andshowing the plane of the hammer relative to the plane of other parts ofthe movement.

Figure l() is a cross section along line 10-10 ot' Fig. 4.

Referring to Figs. 1, 2 and 9, the hammer 1 pivots on a stud 2 screwedor driven into the plate 3, and it is made to oscillate with the alarmlever 4 by means of a pin 5 passing through the plate 3 in an opening 6.This pin is secured to the hammer, whereas it is free in the lever.Conversely, it could be secured to the lever and be free in the hammer.The alarm lover 4 pivots on an extension 7 of the stud 2 and cooperateswith the lever escapement wheel 8 of the alarm. When it passes from theposition shown by dotted and dashed lines D to the position shown infull lines E in Fig. l, the hammer sets the membrane 9 (Fig. 2)vibrating by striking against the stud lil. ribis hammer, whichoscillates above the upper pivot 2o of the balance (and thus also abovethe balance stati, the lever of the movement and the escape wheel of themovement) is cut away underneath in order to allow it to pass over thebalance 11, the hairspring 12, the balance cock 13, the regulator 14 andthe upper cap 15, whereas it is largely chamfered above. The hammer 1also passes over part of the escape wheel bridge 35 during itsoscillation. `The spring bolt 16, permanently secured to the body of thehammer 1 by a rivet 17 permits the removal of said hammer very rapidly.As a matter of fact, said hammer can be gripped by introducing one ofthe branches of the tweezers in the space i3 (Fig. l), which will thuswithdraw the bolt 16 from the groove 19 out in the stud 2. It will beseen immediately from the drawing that putting it back into place isjust as easy.

In this construction, the upper level of the hammer 1 l(i.e., oi itsetiective part) does not project beyond the upper plane of the movement,the height of which has been subjected to no increase, in comparisonwith a watch of the same type having no alarm, owing to the dispositionot the hammer and to the shortening of the balance stati", which can beelected without detriment to the movement. Fig. 9 shows how the level ofthe center of the movement, shown at the left in this ligure, compareswith the level of the hammer.

sin Fig. 3 the hammer 21 the shape of which is of a cut out form, pivotsin 22. It is made to oscillate with the alarm lever 23, which cooperateswith the alarm lever escapement wheel 24, by means of a pin 25, inexactly the same way as that described for Fig. 2.

The two arms 26 and 27 of the hammer are joined together at theeffective part 28 which strikes against the stud 29. They are situatedon either side of the bridge 3() in which pivot the sweep second wheels31 and 32. The upper level of the bridge 3i! determines the maximumheight of the movement; the hammer does not project beyond this level.

When the hammer oscillates, the arm 27 passes over the upper pivot 33 ofthe balance 34 (thus also above the balance, the balance shaft, thelever of the movement and the escape wheel of the movement) and theother arm 2o together with the effective part 28 passes over the upperpivot 35 of the barrel 36 of the movement (thusalso above the barrel ofthe movement) and over the ratchet wheel 37 of the movement, whereas itonly covers permanently a part only of the alarm barrel 3S and of thealarm ratchet wheel 39.

The spring bolt described in the Figs. 1, 2 and 9 can also be applied tothis embodiment.

The invention can be applied to a watch without a sweep second hand.Figs. 4 and 10 show such an eX- arnple.

The hammer 41, pivoting in 42, strikes against the stud 40 andoscillates above the balance 43, the balance cock 44 (thus also abovethe balance stair", the lever of the movement and the escape wheel ofthe movement) and the train bridge 4' (i.e., also above the gears of themovement) in which pivot the wheels 46, 47, 4S and the escape wheel ofthe movement. The so-called center wheel 46 has been displaced in 49 soas to enable the thickness of the train bridge to be reduced in relationto the barrel bridge 5t). The balance cock 44 may always be situatedwithout diculty at a level which is lower than that of the barrel bridgeSe. Here its level corresponds to that of the train wheel bridge 55. Thehammer passes over the components 43 to 49 without increasing thethickness of the movement.

In all the embodiments described, the moment of inertia of the hammercould be increased if it were totally or partially made of heavy metalor of another heavy material (for instance tungsten carbide having adensity of 16 to 17 g./cm.3).

The solutions described above enabling the hammer to be rapidly removedto give access to the regulating members it covers, have thedisadvantage of complicating the pivoting of the hammer, and to requireit to be carried out with particular care.

The Figs. 5 to 8 illustrate another embodiment of an alarm wrist-watchcomprising means arranged to allow, once the movement has been removedfrom the case, the regulating members to be uncovered by causing thehammer to pivot beyond the limit of its habitual angular travel towardsthe exterior of the movement, without removing it.

In the fourth embodiment, illustrated in the Figs. 5 toV 8, as soon asthe alarm device is unlocked, the alarm 1 which pivots on an extension 2of the stud 3 of the hammer 4, oscillates under the action of knownmeans, which have not been shown, and drives the hammer 4 by means of apin 5 passing through the plate 6 through a hole 7. The pin 5, which isfreely adjusted in the lever 1 and in the hammer is provided with anupper groove 8 and with a lower groove 9 the shapes of which aresymmetrical. This pin 5 is maintained engaged in the lever 1, as may beseen in Fig. 6, by means of a roundel 10 which a spring 11 pressesconstantly into the upper groove S. The hammer oscillates from'the posi-Vtion A to the position B (Fig. 5) whilst passing above the balance 12,the regulator 13, the upper cap 14 and the balance cock 15 (thus alsoabove the balance staff, the lever of the movement and the escape wheelof the movement). When it is desired to uncover the balance cock and thebalance, the hammer must be deviated so as to bring it to the positionshown in Fig. 7. in order Cil to do this the pin 5 is raised, forinstance by means of a screw-driver which is introduced into theapparent upper groove S (Fig. 6), in order to bring it to the positionshown in Fig. 8. The withdrawal of the pin 5 from the lever 1, then fromthe hole 6, allows the hammer to be pivoted up to the position shown inFig. 7, which uncovers the balance cock 15 and the components 12, 13,14. To keep the hammer in this position, it is merely necessary to lowerthe pin 5, and its extremity coming into contact with the wall 19 of thenotch 18 in the plate prevents the return of the hammer.

When it is desired to return the hammer to its operating position, thereverse procedure is followed: withdrawal of the pin 5; pivoting of thehammer back to the position B; gentle lowering of the pin 5 until Vit isin contact with the face of the alarm lever 1; pivoting of the hammertowards the position A until the extremity 16 of the pin 5 penetratesinto the opening of the lever 1.

It will be remarked that the watch according to the invention enablesthe obstacles mentioned in the preamble to be largely eliminated:

1st by reducing the mass of the hammer;

2nd by lodging the eifective part of the hammer in otherwise inecientlyutilized portions of the space of the movement;

3rd by constructing and positioning essential components in space savedby reconstructing and positioning the hammer.

What we claim is:

In an alarm wrist watch having a watch movement, including the balance,balance sta", lever of the movement, escape wheel of the movement,barrel of the movement, barrel of the alarm, and the gears of themovement, which extend from the face surface of the watch upwardly to atleast two connecting means spaced at different levels above said face,diaphragm means above the upper level of said movement, hammer meansshaped to t and move within the space between the lower and upper levelsof said movement for striking a part of said diaphragm, means forpivotally mounting said hammer means for horizontal oscillation with theeiective part thereof within said space between the two levels of themovement, said hammer means being positioned to oscillate in saidhorizontal plane and above at least one of said balance, balance staff,lever of the movement, escape wheel of the movement, barrel of themovement, barrel of the alarm and the gearsV of the movement.

References Cited in the file of this patent

